It’s time to set the record straight about the so-called Bulgarian split squat. First, Bulgarian weightlifters never used it. Second, many of the personal trainers and strength coaches who write about how to do it are recommending a variation that does more harm than good. Let me explain.

In 1988 when I was a strength coach for the Air Force Academy, I invited Bulgarian coach Angel Spassov to visit our facility, have lunch and be interviewed for some weight training publications I was writing for at the time. Spassov told me about two leg exercises he thought would be very useful for my athletes. One exercise was the high step-up, and the second was a split squat with the back foot elevated, which many strength coaches later referred to as the Bulgarian lunge.

The step-up recommendation got the most attention in the strength coaching community. The Russian weightlifter Leonid Taranenko, who still holds the record for the all-time best clean and jerk – 266 kilos (586.4 pounds) –occasionally performed high step-ups when he felt his lower back was excessively fatigued from squats. Taranenko reportedly used up to 180 kilos (396 pounds) in step-ups. Because the torso is more perpendicular to the floor during step-ups as compared to squats, it follows that the erector spinae muscles would not have to work as hard and the compressive forces on the disks would be lower.

At the time Spassov was touring the country and promoting these two exercises, a colleague of mine asked Taranenko if he had replaced squats with step-ups and if he had gotten the idea of doing step-ups from Coach Spassov. Taranenko replied that he still did back squats and that he had never heard of Angel Spassov! During my 90-minute interview with Spassov, which I had taped and listened to many times, Spassov never said that the elite Bulgarian lifters had stopped doing squats in favor of step-ups or split squats. I also attended a presentation Spassov gave in Denver to a group of strength coaches, and he never said that Bulgarian weightlifters, or any Russian weightlifters, had given up squats in favor of these two exercises. Maybe Spassov made such a claim to someone else, but I don’t have any evidence that he said it. That’s my perspective – come to your own conclusions. OK, on to the split squats.

When Spassov told me about the split squat with the rear foot elevated, I asked him to watch me teach it to one of my female athletes. When I placed her back foot on top of a multipurpose bench, he looked at me as if I had stepped on his dog. “No! No! No!” he warned me. He told my athlete to rest her back leg on a nearby stack of several weight plates that was about 4-6 inches high – just high enough to put more emphasis on the front leg while also enabling her to place the ball of her foot on the platform for increased stability. That’s the bottom line: If you want to do a true “Bulgarian split squat” or, perhaps more appropriately named, an “Angel Spassov split squat,” your back foot should be resting on a platform about 4-6 inches high.

The first athletes I had try this exercise were several of the nationally ranked ice dancers who were training at the Air Force Academy at the time. One was Gorsha Sur, a former junior champion from Russia who teamed up with former US national champion Renée Roca. When I showed the exercise to Sur, he told me that it would be better for ice dancers to elevate their rear foot at least 12 inches and to hold the bar in front (as you would with a front squat) to simulate the position the torso and back leg often gets in during ice dancing routines. Since this variation was different from the one Spassov had shown me, I decided to call it the Gorsha lunge; I subsequently wrote about it for the international skating magazine Blades on Ice. Just for the heck of it I also had a few swimmers at the Academy try this exercise, and the next day several of them told me, “Coach, my Gorshas are soooooo sore!”

I’ve seen articles in which coaches prescribe “Bulgarian lunges” with the back foot elevated extremely high to maximize the work of the front leg. There are two problems with this. First, this position gives the athlete much less stability. When is foot is not elevated, the lifter can more safely handle greater weight. In fact, at the Air Force Academy I had Chad Hennings, the 1987 Outland Trophy winner, perform a split squat with the back foot on the floor; he was able to perform the exercise, all the way down, with 229 kilos (505 pounds)! I also had a female weightlifter on my team who weighed 60 kilos (132 pounds) perform the exercise with 93 kilos (205 pounds). The point is, you give up a lot of the strength training effect the higher you lift the back leg.

A worse problem is that by elevating the back leg, you hyperextend the spine and create unnatural shearing forces on it. The farther down you squat and the more resistance you add, the greater the stress. Further, lifters who have excessive anterior pelvic tilt are apt to experience issues with the muscles of the anterior chain, such as the psoas, rectus femoris and rectus abdominus – along with spasms in the erector spinae. One strength coaching colleague of mine said that lifters who have one hip higher than the other can experience SI joint problems with such exercises.

Maybe there are some athletes who won’t incur problems from performing this exercise with the foot elevated higher than six inches, but I’m doubtful. More likely they’ll soon be getting regular visits from invisible gnomes jumping up and down on their fifth lumbar vertebrae and Googling terms such as sports hernia.

Now there is the question of adding resistance. If you perform the exercise with dumbbells, you’ll be fine – if you lose your balance, you can simply drop the dumbbells. However, to make progress, you’ll probably switch to a barbell eventually. To use heavy weights safely you should perform the exercise inside a power rack, with the safety pins set at an appropriate height. Because lateral stability is compromised on this exercise, a trainer would spot this exercise from behind (because a front spotter can only act as a rep counter). If two spotters are available, then one on each side is best; with three, you would have one on each side and one behind.

Although there may be some lifters who can perform this type of split squat for months at a time without any problem, I’ve found it best to vary it with other types of lunges after several weeks. What I found at the Air Force Academy working with hundreds of athletes on split squats is that after two weeks of heavy weighted split squats, many athletes began complaining of tender knees.

About four years ago Ivan Abadjiev, the founder of the Bulgarian method of weightlifting, visited Rhode Island, and I asked him about his views on training. When we talked (through an interpreter) about Bulgarian split squats, he assured me that he never had his weightlifters perform them. So, no, they cannot replace squats. Nevertheless, split squats with the rear foot elevated slightly have value if performed properly and in moderation.